Crane and derrick.



0. N. GARDNER.

CRANE AND DERRIGK.

APPLIOATION FILED MAR. 15, 1912.

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AENT FID,

CRANE AND DERRICK.

Specification of Letters Patent.

Patented Oct. 15, 1912.

Application led March 15, 1912. Serial No. 683,973.

To all whom t may concern:

Be it known that I, OMAR N. GARDNER, a citizen of the United States, residing at Jamestown, in the county of Chautauqua and State of New York, have invented certain new and useful Improvements in Cranes and Derrcks, of which the following is a specification. i

This invention relates to certain new and useful improvements in that type of hoisting mechanism known as cranes and derricks, and the invention consists, essentially, of a crane or derrick having a pivoted boom and having a pivoted jib adapted to travel thereon and to adjust itself thereon in unison with the vertical adjustment of the boom, and means including a hoisting block and cable suspended from the boom and connected to the jib for raising and lowering the load and also raising the boom about its pivotal center by the same means which raises and lowers the load and while the load is not engaged.

rfhe invention further consists of the parts and the constructions, arrangements and combinations of parts which I will hereinafter describe and claim.

In the accompanying drawing forming part of this specification and in which similar reference characters indicate like parts in the several views; Figure l represents a side elevation of a crane or derrick embodying the salient features of my invention, showing in full lines the position' of the hoisting block when adjusting the height of the boom, and showing in dotted lines the position of the block when ready to receive a load. Fig. 2 is a detail to be referred to. My invention is applicable to any of the well known forms of cranes or derricks whether of the rotary or so-called stiff leg type or to any arrangement of hoisting mechanism employing a pivoted boom and hoisting block and cable.

In the present drawing I have shown my several improvements applied to a stiff leg derrick having the usual vertical mast, A, suitably stepped for rotation at its lower end and having its upper end connected to the brace or stiff leg, B. This arrangement may be treated as illustrative of any well known style of hoisting mechanism and to this end the mast may represent any vertical support for the boom, jib and other parts going to make up a modern hoisting apparatus of the character specified.

The boom, B, may be of any well known form and construction and it has its lower end mounted upon the shaft, C, which forms the center about which the outer end of the oom may be raised and lowered, said boom having journaled in its outer end the pulleys, D, D, over the outermost, D, of which the cable, E, from a suitable winding drum, not shown, passes. After passing over the pulley, D, the winding cable passes around any well known and approved form of hoisting block, F, from whose bail, G, depends the hook, H, or equivalent means for engagfing and suspending the load to be handled,

`said cable thence passing over the pulley, D, and finally extending along the boom land being secured to the lower or outer free `:end of the jlb, I. This jib mayV be conlstructed n any appropriate manner; its uplper or inner end is pivoted to the upper portio-n of the mast or support, A, and its lower or outer end straddles the boom and is provided with flanged wheels, J one at each side, the flanges of which extend over the outer sides of the boom and thereby accurately guide this end of the jib in its traveling movement on the boom, and also, brace the same against lateral or side strains. The hub portions of the flanged wheels, J, bear up under the boom, and the outer end of the hoisting cable is attached to this end of the jib.

The shaft, C, upon whichthe boom turns in raising and lowering, carries a sprocketwheel, K, and in the upper or outer portion of the boom is j ournaled .the sprocket-wheel, L; a sprocket-chain, M, passes around the sprocket-wheels, K and L, and under the flanged wheels, J, and has its ends connected to the jib at a point above the lower outer end thereof, and in order to keep this chain at the proper tension and to take up any slack which may occur therein, a turnbuckle, N, or other suitable well known belttightening means may be let into the length of the chain at some suitable point. In the drawing, the turn-buckle forms the means for attaching one end of the sprocket-chain to the jib. The shaft, C,will in practice also carry a suitable sliding clutch, R, which is non-rotatably mounted on the shaft C and is actuated by a lever, O, and by the operation of which the sprocket-wheel, K, may be made loose or fast; when the sprocket is made loose, the boom is permitted to lower about said shaft, and when the sprocketwheel, K, is made fast, the boom is held at any point of its adjustment.

The operation of this crane or derrick 1s substantially as follows: The usual winding drum is operated to pay out the cable and the hoisting block is lowered to permit the load to be engaged. The drum is now operated to wind up the cable and this raises the load suspended from the hoisting block, an operation well known in this art.

A leading feature of my invention is to economize in the construction and operation of cranes and derricks and other like devices employing a boom, by dispensing with the separate drum now commonly employed in said devices for raising and lowering the boom, and using the same winding drum and cable and hoisting block for both raising the load and adjusting the height of the boom and the position of the jib. To this end I employ the traveling jib which is connected to the cable and bears under the boom and is adapted to adjust itself thereon cordinately with the change in the inclination and thereby the height of the boom. p

If it is desired to change the boom from a higher to a lower position, the hoisting block is raised into engagement with the boom, as shown in Fig. l and the clutch is released to make the sprocket-wheel, K, loose and as the outer end of the boom lowers, the under side of said boom bears against the flanged wheels and through the latter correspondingly lowers the jib and thereby moves the sprocket-chain, the said wheels traveling against the under side of the boom during this operation; during this movement the sprocket-chain maintains the outer end of the jib in its traveling engagement with the boom. After the desired adjustment has been obtained, 4the clutch is operated to make the sprocket-wheel fast to hold the boom so that the load may be raised and lowered in the well known manner and substantially as before described.

If it is desired to raise the boom from a lower to a higher position, the clutch, R, is thrown out of gear with the lower sprocket wheel and the winding drum is operated and through the hoisting cable the hoisting block, F, is raised until a suitable stop or buffer, F which it carries, engages under the outer end of the boom when the continued winding of the cable results in the outer end of the boom and jib being raised until the boom reaches the desired elevation, at which point it is held by the clutch mechanism before mentioned. The same winding drum' may now be operated to pay out the cable, when the hoisting block will lower to enable it to be engaged with the load, after which said cable is again wound to lift said load.

By the construction shown and described, I am enabled to use one winding drum and cable for both raising and lowering the load and raising and lowering the boom, and accordingly the separate winding drum now commonly employed for raising and lowering the boom is dispensed with. This reduces the amount of machinery required in devices of this character, and it reduces to a minimum the expense of operating such devices. The sprocket-chain also acts as a truss for the boom and accordingly strengthens the same.

I-Iaving thus described my invention what I claim as new and desire to secure by Letters Patent is 1. In a device of the character described, the combination with a hoisting block, a cable therefor, a vertical support, and a. boom adapted to be raised and lowered about its inner or lower end, of a traveling jib pivoted to the support and connected to the cable, and having its outer or lower portion embracing the boom and traveling in contact therewith, and means for lowering the j ib to allow the boom to be lowered, said jib adapted to shift its posit-ion on the boom, in response to a change in the inclination of said boom, said means comprising a flexible element extending along the boom, and wheels at opposite portions of the boom over which sa id element passes, said element having its ends attached to the outer or lower portion of the jib.

2. I n a device of the character described,

the combination with a hoisting block, a cable therefor, a vertical support, and a boom adapted to be raised and lowered about its inner or lower end, of a traveling j ib pivoted to the support and connected to the cable, and having its outer or lower portion embracing the boom and traveling in contact therewith, and means for lowering the jib to allow the boom to be lowered, said iib adapted to shift its position on the boom, in response to a change in the inclination of said boom, said means including sprocketwheels at opposite portions of the boom, and a sprocket-chain having one end secured to an outer portion of the jib, said chain extending upwardly over one of the sprocket-wheels and returning downwardly along the boom and under the outer end of the jib and around the other sprocket-wheel, and returned upwardly along the boom and having its other end secured to said jib.

3. In a device of the character described7 the combination with a hoisting block, a

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cable, and having its outer or lower portion embracing the boom and traveling in contact therewith, and means for lowering the jib to allow the boom to be lowered, said jib adapted to shift its position on the boom in response to a change in the inclination of said boom, said means including sprocketwheels at opposite portions of the boom, and a sprocket-chain having one end secured to an outer portion of the jib, said chain eX- tending upwardly over one of the sprocketwheels and returning downwardly along the boom and under the outer end of the jib and around the other sprocket-wheel, and returned upwardly along the boom and having its other end secured to said jib, and means for adjusting the tension of said chain.

t. In a crane, derrick or like device, the combination of a vertical support, a pivotally mounted boom, a jib having its outer end mounted in traveling engagement with the underside of the boom, a winding-cable extending along said support toand over the end of the boom, and having its outer end connected to the outer portion of the jib, and a hoisting block suspended from an intermediate portion of the cable and arranged to engage the outer end of the boom during the winding of said cable to thereby change the inclination of the boom, said jib shifting its position on the boom in response to the change in the inclination of said boom.

5. In a crane, derrick or like device, the combination of a vertical support, a pivctallyy mounted boom, a jib having one end pivotally mounted on the support and having its other end provided with a pulley which engages t-he boom from below, a winding-cable extending from said support to and over the outer end of the boom and having its outer end connected to the outer portion of the jib, and a hoisting block suspended from an intermediate portion of the cable and arranged to engage the outer end of the boom during the winding of said cable to thereby change the inclination of the boom, said jib shifting its position on the boom in response to the change in the angle of said boom.

G. A crane or derrick having a boom, a vertical support, a jib between the boom and support and pivotally secured to the latter, and a winding-cable and hoisting block, said block being suspended from an intermediate portion of the cable and arranged to engage the boom when the cable is wound to thereby elevate the boom and adjust its height, and said jib being connected to the outer end of the cable and adapted to travel on the boom, and change its position relatively thereto in response to a change in the inclination of said boom.

7 A crane or derrick having in combination a vertical support, a boom pivotally mounted at its lower end on said support, and having sprocket-wheels journaled in opposite portions, a chain passing around said sprocket-wheels, one of said sprocket-wheels having a clutch member to be engaged by the rst named member, a jib pivoted to the support having its outer end embracing the boom between its ends and having a roller traveling in contact with the underside of the boom, said chain having its opposite ends attached to said jib near the outer end thereof, a cable and a hoisting block, pulleys in the outer end of the boom around which the'cable passes, said cable having its outer end connected to the jib, and said pulley block having a buffer adapted to contact with the underside of the boom when the cable is wound whereby the further winding of the cable elevates the boom, said hoisting block having means for suspending a load.

In testimony whereof I aHiX my signature in presence of two witnesses.

- OMAR N. GARDNER. Witnesses:

T. `WALTER FowLEn,

C. W. FowLnR.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

